Weather forecasting tough this fall

The last 2 months of summer weren't pretty, with heat and rain at record-low levels of scarcity. But, along comes this past weekend, when some pockets of southern Indiana saw more than 7 inches of rain.

Such is the trend -- or lack thereof -- when there's so little direction from traditionally key weather indicators, like the Southern Oscillation Index (SOI), or the weight toward either La Niña or El Niño conditions. As a result, figuring out how and when the fall weather's going to change is anything but easy, says one Corn Belt weather expert.

"This is a time when we should be cautious about looking too far into the future, especially when we don't have a dominant driver," says Dev Niyogi, state climatologist based at Purdue University, in a university report. "There are some years when we have very strong indicators. When El Niño and La Niña are active, they tend to dictate the weather of our upcoming season, and we can project with higher confidence whether it will be warmer or drier."

There is one indicator that could foreshadow fall and early winter weather still in play despite a lack of direction from the SOI, Niyogi says. But it's still clear as mud at this point, he adds.

"If we have a tropical atmosphere becoming more active, then we can expect more warmer and humid weather conditions, with more storm activity. On the other hand, if that is not the dominant factor, then we might have the potential for a colder, drier air mass coming to Indiana more frequently," he says in a university report. "And therein lies our dilemma at this point in drawing one strong, singular conclusion as to what will dominate. But one thing that we can say for certain is in the absence of one strong driver and that we will be influenced by multiple air masses, it is very likely that Indiana will witness wide swings in its week-by-week weather as we go into the new season."